The Defense Advanced Research Projects Agency, better known as DARPA, is looking for a “secure messaging and transaction platform” that would use the standard encryption and security features of current messaging apps such as WhatsApp, Signal, or Ricochet, but also use a decentralized Blockchain-like backbone structure that would be more resilient to surveillance and cyberattacks.

DARPA’s goal is to have “a secure messaging system that can provide repudiation or deniability, perfect forward and backward secrecy, time to live/self delete for messages, one time eyes only messages, a decentralized infrastructure to be resilient to cyber-attacks, and ease of use for individuals in less than ideal situations,” according to a notice looking for proposals, which was recently posted on a government platform that offers federal research funds to small businesses.

In other words, as a security researcher put it, DARPA wants “a public wall anyone can monitor or post messages on, but only correct people can decrypt.”